Process for flocculating positively charged emulsoids from a disperse medium



Patented 'June 20, 1933- UNITED STATES PATENT; OFFICE OLIVER I. URBAIN,OF COLUMBUS, OHIO, ASSIGNOB '10 CHARLES H. LEWIS, OF

HABPSTEB, OHIO PROCESS FOR I'LOCGULATING POSlI'IIVELY cannon]; nuutsomsmom a DISPERSE MEDIUM No Drawing. Application filed June 7,

This invention relates to and it is the object of the invention toprovide a process for fiocculating positively charged emulsoids from adisperse medium.

The term emulsoids as employed herein may be defined as solvatedcolloids, which may be dispersions of solids within a liquid, or of aliquid within a liquid. They are organic in constitution.

p In order to flocculate emulsoids it is first necessary to bring themto their critical potential, as well as to their critical hydration. Thecritical potential need not necessarily coincide with the isoelectricpoint. The critical hydration point is that point in the hydration ofthe emulsoids at which they will flocculate, providing they are at theircritical potential.

An important feature of the present invention, therefore, relates to thedesolvation or deh dration of the emulsoids in the disperse me ium.Specifically, the invention contemplates the displacement of theadsorbed solvating water film of the emulsoids by molecules for whichthe nucleus of the emulsoid has a greater affinity than it has for thewater molecules of the. solvating film. In other words, the inventioncontemplates the removal of the solvating water film by the phenomena ofpreferential adsorption.

so that preferential adsorption will take 7 place. It is furtheressential that the positive ends of the molecules used to displace thewater molecules must not be subject to solvation. Furthermore, the waterdisplacing molecules must not be dissociated to any appreciable extentin the watei of the disperse medium,

It is, of course, possible to flocculatc emulsoids without desolvationor dehydration by 1932. Serial N0. 615,950.

salting out but in so doing, enormous quantities of salts are reguired,in comparison to the quantity require when the emulsoids are firstde-hydrated. For instance, to effect flocculation of agar a ar, anemulsoid, one mol per liter of anhy rous MgSO; is required. If, however,the agar agar is first desolvated' or dehydrate d, it can be flocculatedby the addition of one millimol per liter of the same salt. Theimportance, therefore, of desolvating or dehydrating the emulsoidsbecomes at' once apparent.

According to the present invention, the solvatmg water film of thepositively charged emulsoid is displaced by incorporatin in the dispersemedium alkyl esters of po ycyclic acids. It is contemplated that eitheralkyl esters of polycyclic carboxylic acids, or a1 1 esters ofpolycyclic sulfonic acids may e useid. th d I n ese compoun s the 01 cclic rou is in the ne ative end of th d ni ol ecule i; negative on s ofthe molecules of these com pounds are preferentially adsorbed over the 7coo. oH,)..oH= or owmooocmu which is hexyl l-napthoate.

000401394011, or oumooooin'u which is amyl l-anthroate.

The alkyl esters of polycyclic sulfonic acids have the general formulaAr. C0,.R in which 3r is also a polycyclic residue or radical,

is also an alkyl group made up of G and H in the proportion of C HExemplary compounds conforming to the last above general formula are,

LOJJHLOHaOHaOH; or OMHLBOLOOH! which is butyl l-napthalenesulfonate.

which is hendecyl 2-anthracenesulfonate. I The above compounds areprepared by the reaction of an acid chloride of a polycyclic A specificexample of this reaction is that between napthoyl chloride and amylalcohol, which is as follows, and forms amyl napthoate,

61911 -0001 C5H11OH 1o 1- s 11mc1 The neral reaction for forming alkylesters o polycyclic sulfonic acids is:

positiv solution to permit the flocculation of the desolvatedordehydrated emulsoids b a suitable electrolyte and the final coaguation of the flocculated material.

A specific illustration of the application of the rocessis as follows:Assum' that it is deslred to remove the positively charged emulsoidcontent from a waste liquid, whlch el charged emulsoid content has a tenday bio chemical oxygen demand of 250 to 300, the desolvating ordehydrating compound, for example hexyl l-napthoate should be added'inliquid form in an amount from 40 to pounds per million allons of waste.Thereafter, the waste'shoul be agitated for a period of from two to fourminutes, and

then have incorporated therein an electrolyte havinga hi h valent anionand low valent cation such or example as sodium sulfate or sodiumphosphate, which will function to neutralize the positive charge carriedby the desolvated emulsoid in the acid solution. The flocculatedmaterial will readily settle out, or may beremoved by filtration.

Of course, the quantity of the compound necessary to d'esolvate ordehydrate the positively charged emulsoids, will vary with theconcentration of the emulsoids in the liquid to be treated. To determinethe exact amount of the desolvating or dehydrating com ound to employ,it is only necessary to ma e up a solution of the compound of knownstrength, and-add this solution to a known volume of the emulsoid disrsion in gradually increasing amounts an izheck the reading on anephelomeper with a colorimeter attachment, until no further turbidityincrease is noticed. This will be the point at which desolvation ordehydration is complate, and the necessary quantity of the compoundrequired can thus be computed from A specific example of this reactionis that between l-napthalenesulfonate chloride and butyl alcohol, whichis as follows, and forms butyl l-napthalenesulfonate,

While the step of desolvating emulsoids to facilitate their flocculationas wide adaptation, it is of especial utility with respect not only theinitial step of desolvating the emulsoids by the incorporation in thedismedium of a compound as hereinbeore described, but also comprehendsthe additional steps of controlling the pH of the the known volume ofthe known strength solution of the compound used in the experiment.

What I claim as my invention is:

1. In a process for flocculating positively charged emulsoids from thedisperse medium, the step which comprises incorporating in the dispersemedium, an alkyl ester of a polycyclic acid.

2. In a process for flocculating positively charged emulsoids from thedisperse medium, the step which comprises incorporating in the dispersemedium, an alkyl ester of a polycyclic carboxylic acid.

3. In a process for flocculating positively charged emulsoids from thedisperse medium, the step which comprises incorporating in the dispersemedium, an alkyl ester of a polycyclic sulfonic acid.

4. In a process for flocculating positively charged emulsoids from thedisperse medium, the step which comprises incorporating in the dispersemedium hexyl l-napthoate.

5. In a process flocculating positively charged emulsoids from thedisperse medium, the step which comprises incorporating in the dispersemedium lbutyl l-napthalenesulfonate.

6. A process for flocculating positively charged emulsoids from adisperse medium, comprising incorporating in the disperse medium, analkyl of a polycyclic acid, then agitating, incorporating calciumhydroxide to bring the pH of the solution to from 8.5 to 9.5, thereafteradding a suitable electrolyte with further agitation, and finally addinga suitable coagulant.

7. A process for flocculating positively charged emulsoids from adisperse medium, comprising incorporating in the disperse medium analkyl ester of polycyclic carboxylic acid, then agitating, incorporatingcalcium hydroxide to bring the pH of the solution to from 8.5 to 9.5,thereafter adding a suitable electrolyte with further agitatlon andfinally addin a suitable coagulant.

8. A process or flocculating positively charged emulsoids from adisperse medium, comprising incorporating in the disperse medium analkyl ester of a polycyclic sulfonic acid, then agitating, incorporatingcalciun hydroxide to bring the pH of the solution to from 8.5 to 9.5,thereafter adding a suitable electrolyte with further agitation andfinally adding a suitable coa ulant.

OLIVER URBAIN.

